In literature and film the keyhole is a popular symbol for secrets and hidden mysteries, windows into other worlds, curiosity, a quest for the truth, discoveries and suspicions. Most often when looking in from the outside. But due its predictability and frequent repetition, this symbol is more or less exhausted.

The keyhole is interesting as a symbol of the impossibility of a complete and clear-cut interpretation of what is seen. Blind spots can be replaced with new meanings.
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